GOODWILL AND INTANGIBLE ASSETS - Narrative (Details)	12 Months Ended
Sep. 30, 2022 USD ($) year	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Impairment Effects on Earnings Per Share [Line Items]
Goodwill additions	$ 0
Impairments of goodwill	0	$ 0	$ 38,300,000
Goodwill	45,653,000	45,653,000
Amortization	7,200,000	$ 7,200,000	$ 7,200,000
Expected amortization in 2023	6,600,000
Expected amortization in 2024	$ 6,400,000
Valuation Technique, Discounted Cash Flow \| H&P Technologies \| Expected cash flow period
Impairment Effects on Earnings Per Share [Line Items]
Reporting unit, measurement input \| year	5
Valuation Technique, Discounted Cash Flow \| H&P Technologies \| Measurement input, discount Rate
Impairment Effects on Earnings Per Share [Line Items]
Reporting unit, measurement input	0.14

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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